Modular Multilevel Converter (MMC) For Motor Drive Applications

Abstract

The first chapter has demonstrated on the state of art of multilevel converter technology. Fundamental multilevel converter structures and modulation paradigms has been discussed. The focus has addressed classical, modern and more practical industrial application of multilevel converters such as Neutral Point Clamped Converter (NPC), Cascaded H-bridge (CHB) Converter and Flying Capacitor (FC). The overview on Pulse Width Modulation algorithm is presented. The second chapter overview on operation principle of Modular Multilevel Converter (MMC) and impact of its elements is done. Comparison of MMC with CHB converter in point view of advantages and disadvantages is presented. At the end of this chapter literature review has been focused on the previous work of MMC for drive applications.In chapter three, discusses on phase shifted pulse width modulation and capacitor voltage balancing technique for five-level modular inverter will be done. The modulation and balancing strategy presented are confirmed by simulation and results are discussed. The fourth chapter focused on MMC for drive applications. Using MMC for drive applications, each module will require capacitor value at low frequency operation which is described in this chapter with details of theoretical analysis has been shown to operate the converter for low frequency operation of drives without requiring any change in hardware. The aim of this chapter is to propose an optimization way for overcoming the problem of Modular Multilevel Converter (MMC) at low speed for Induction motors. Meanwhile comparison between two proposed methods at low frequency has been presented.In the fifth chapter conclusion based on the whole work and special on the last two chapters is done.